LCD rot?

On Fri, Jul 26, 2013 at 9:56 AM, Geoffrey Oltmans <oltmansg at gmail.com> wrote: If there's a black line consisting of a full line or lines of pixels, that's most likely caused by either a fault in the driver for that line, or a failure of the electrical connection. Cycling the pixels won't help with that. There's a lesser chance of dead lines being caused by having a DC bias on that line for an extended period, which shouldn't happen except in a failure of the LCD controller. Cycling the pixels could help with that, but if the controller failed to cause it, it's unlikely that the controller has started working correctly again. Since this kind of failure only occurs when the LCD is powered up with the controller not working for an extended period of time, it's not going to result from having the LCD being stored unpowered for an extended time. The black blob problem, which usually eventually reaches the all-black case, is caused by a chemical change (oxidation?) of the liquid crystal material, and I don't think there's anything you can do electrically that's going to fix or even reduce the problem. AFAICT that's caused by the seal failing, which can be caused by temperature extremes, but sometimes just happens as a result of aging. It can also be caused by mechanical pressure between the glass layers, but leaving it sit for a few years, even with wide temperature swings, shouldn't cause it in that manner.